Two traditional types of optical buffers,the feed-forward(FF) type and the feed-back(FB) type,are analyzed based on the maximum buffering time restriction,the delay granularity restriction,and the packet length limitation,which affect the optical buffer performance.Analysis results demonstrate that these limitations restrict each other and prevent the optical buffer performance from being further improved.An adaptive elastic fiber loop optical buffer(E-FLOB) is put forward,which has merits of both FF and FB...